1. Field of the Invention
The present invention relates to an adjustable hook and chain to provide adjustable length and tension in a load securing system for use in storing, securing, and handling cargo in such activities as construction, cargo hauling and storage, and securing a roll on/off dumpster to a dumpster hauling truck or freight to commercial trucks and flat bed trailers.
2. Description of the Related Art
Tasks involving handling heavy loads are frequently time consuming and frustrating to complete. For example, securing cargo to a commercial truck, a crane hook to a load, hitching a trailer to a truck, and attaching a drag cable to a roll on/off dumpster for hauling onto a dumpster truck all involve precision tasks wherein some kind of attachment or securing device is positioned precisely and carefully relative to the position of the cargo. Time is frequently wasted because, for example, a chain is slightly too short or too long to safely to tie down a load to a flat bed truck. Frustration can result, for example, when a dumpster securing cable is slightly too short to attach to a trash filled roll on/off dumpster forcing the operator to return to a dumpster truck to wind off a few more inches of cable to successfully connect up to the dumpster. Hence, there is a need for a safe and adjustable chain or cable that can provide a few inches of adjustable play, in either direction, in a cable or chain to assist the operator in securing, for example, a load to a trailer or a truck to a trailer.
Several efforts have been made to address these problems. U.S. Pat. No. 1,119,636 issued Dec. 1, 1914 to P. C. Richter, describes a hook and chain coupling having a link secured thereto via a removable pin type connector. However, the ""636 coupling is not adjustable.
U.S. Pat. No. 1,295,738 issued Feb. 25, 1919 to G. D. Hagar, describes a grip chain coupling with a threaded hook element. The ""738 device is not adapted for use in securing cargo and, in particular, to tying down and securing cargo to moving vehicles. More particularly, the ""738 device does not provide a safety feature that informs the user when the device is being used in a safe or, more pertinently, unsafe manner.
U.S. Pat. No. 5,159,729 issued Nov. 3, 1992 to W. T. Walker, describes a tie-down device for securing and holding down cargo. The device includes a turnbuckle. A strap is provided having a first end and a second end that are secured to the turnbuckle, so as to loop back on itself thereby defining a loose strap and a stationary strap. A first hook is carried by the turnbuckle. A second hook is carried by the strap between the loose and stationary straps. Rotation of the turnbuckle in a first tightening direction wraps the loose strap around the stationary strap, shortening the loose strap for tightening the device and securing and holding down the cargo and also locking the loose strap in place. Rotation of the turnbuckle in a second loosening direction unwraps the loose strap from around the stationary strap, lengthening the loose strap for untightening the device and unsecuring and releasing the cargo. The ""729 tie-down device is overly complicated to use and relies on failure of the stationary strap in preference to the loose strap to inform the user that the tie-down device is being used in an unsafe manner. There is a need for a less complicated and safer to use tie-down device.
Other patents showing devices or apparatus for handling loads or cargo but which do not solve the above mentioned problems include U.S. Pat. No. 1,410,770, issued Mar. 28, 1922 to H. Silverman (fastening device for necklace); U.S. Pat. No. 2,552,219, issued May 8, 1951 to R. W. Schleicher (die lifting hook); U.S. Pat. No. 2,640,506, issued Jun. 2, 1953 to P. C. Consoletti (harness frame suspending device); U.S. Pat. No. 2,651,533, issued Sep. 8, 1953 to C. Miller (swivel); U.S. Pat. No. 2,801,120, issued Jul. 30, 1957 to H. Shepard (swivel joint for aluminum boat fittings); U.S. Pat. No. 2,812,971, issued Nov. 12, 1957 to J. H. Teutsch (hoist lift connection for dies); U.S. Pat. No. 3,009,500, issued Nov. 21, 1961 to A. E. Russell (adjustable anti-skid chains); U.S. Pat. No. 3,282,045, issued Nov. 1, 1966 to Y. Thelan (means for an eye-link for chains); U.S. Pat. No. 3,511,527, issued May 12, 1970 to R. L. Gower (head for weldless connectors); U.S. Pat. No. 3,677,424, issued Jul. 18, 1972 to W. G. Anderson (invalid lifting apparatus); U.S. Pat. No. 4,910,833, issued Mar. 27, 1990 to Barbour et al. (double-locking anchor chain tensioner); and U.S. Pat. No. 5,778,827, issued Jul. 14, 1998 to M. O. Hansen (cow lift mechanism).
None of the above inventions and patents, taken either singularly or in combination, is seen to describe the instant invention as claimed. Thus, an adjustable hook and chain to solve the aforementioned problems is desired.
In one aspect of the invention an adjustable chain comprises an elongated flexible member such as a chain, rope or cable attached to an adjustable hook.
In another aspect of the invention, the adjustable hook comprises: a female shank, wherein the female shank has a hollow bore comprising a first shank thread, an upper end and an opposite lower end; a male longitudinal member comprising an upper region with a first male thread that complements the first shank thread, and a lower region, wherein the upper region is adapted to fit inside the bore; and a hook on the lower region of the male member.
In one form of the invention, the elongated flexible member is attached directly or indirectly via a first attachment mechanism to the upper end of the female shank. A hook is attached directly or indirectly via a second attachment mechanism to the lower region of the male member to provide the adjustable chain. When the male member is screwed into or out of the female shank the hook position may be varied relative to the female shank thus lengthening or shortening the adjustable chain. If both ends of the adjustable chain are attached to fixed points, the tension in the adjustable chain is varied when the male member is screwed into or out of the female shank. A turning member is optionally used to rotate the female shank or male member without rotating the hook or elongated flexible member thereby allowing an operator to easily vary the length of the adjustable chain to secure a load, for example, to a truck.
In one embodiment of the invention, the first male thread comprises a polit hole positioned to provide notice when the male member is over extended from the female shank.
In a further embodiment, the upper region of the male member comprises a male member widened section with a second male thread, and the female shank comprises a widened shank section with a second shank thread which complements the second male thread. The widened shank section is adapted to accommodate the male member widened section.
In a still further embodiment of the invention the widened shank section comprises an internal shank flanking ledge, and the male member widened section comprises a complementary flanking ledge, wherein when the complementary flanking ledge abuts the internal shank flanking ledge, the longitudinal male member is prevented from exiting further from the female shank.
In another embodiment of the invention, the female shank comprises an internal face, and wherein the widened section further comprises a top face. The top face abuts against the internal face when the male member is fully screwed into the female shank thereby providing notice to stop screwing the male member into the female shank.
These and other embodiments of the present invention will become readily apparent upon further review of the following specification and drawings.